The effect of enzyme concentration on physcical characteristics of pumpkin (Cucurbita moschata) puree and its dried extract

Abstract

Pumpkin (Cucurbita moschata) contain many nutritional and biologically active components such as carotenoid content, polysaccharides, sterols, vitamins and protein. Since pumpkin has perishable characteristics, pumpkin must be preserved to increase the shelf life. The present study describe the possibility of producing spraydried pumpkin extract to increase the shelf life. Since pumpkin have high viscosity, it tend to cause deposit in the wall of spray drying chamber. With the help of enzyme liquefaction technique, the viscosity of the pumpkin can be reduced. In this research, pumpkin puree were individually treated with Pectinex Ultra-SP (0-2.5% w/v). Then, concentration Pectinex Ultra SP that produce the best viscosity reduction of pumpkin puree were chosen and treated with Celluclast 1.5 L (0-2.5% w/v). The results showed that 2.5% w/v of both Pectinex and Celluclast 1.5 L produced high viscosity reduction, clarity, total soluble solid and low pH. Then this pumpkin extract are subjected to spray drying condition and physical properties are measured. The spray drying of pumpkin extract with 2.5% w/v Celluclast 1.5 L and 2.5% w/v of Pectinex Ultra SP showed the higher yield of pumpkin powder, while no differences in moisture content, water activity and colour.